Shock absorbing lattice structure produced by additive manufacturing

Abstract

An energy absorbing lattice structure having a predetermined energy absorbing load vector, may include, in combination, a first lattice substructure comprised of a first set of interconnected struts, and, interwoven with said first lattice substructure, a second lattice substructure comprised of a second set of interconnected struts.

1 . An energy absorbing lattice structure having a predetermined energy absorbing load vector, said lattice structure comprising, in combination:
 (a) a first lattice substructure comprised of a first set of interconnected struts; and   (b) a second lattice substructure interwoven with said first lattice substructure, the second lattice substructure comprised of a second set of interconnected struts,   wherein struts that are substantially perpendicular to the predetermined energy absorbing load vector are excluded from said second lattice substructure, and/or wherein struts that are substantially parallel to the predetermined energy absorbing load vector are excluded from said second lattice substructure.   
     
     
         2 . The lattice structure of  claim 1 , wherein said first lattice substructure and said second lattice substructure are interconnected with one another. 
     
     
         3 . The lattice structure of  claim 1  produced by a process of additive manufacturing. 
     
     
         4 . The lattice structure of  claim 1 , wherein said first and second lattice substructures are formed from the same material. 
     
     
         5 . (canceled) 
     
     
         6 . The lattice structure of  claim 1 , wherein
 said first set of interconnected struts and said second set of interconnected struts differ in diameter from one another;   optionally, said first set of interconnected struts comprises struts of differing diameters; and   optionally, said second set of interconnected struts comprises struts of differing diameters.   
     
     
         7 . The lattice structure of  claim 1 , wherein a stiffness of said first lattice substructure is sufficiently different from a stiffness of said second lattice substructure along said predetermined energy absorbing load vector, so that buckling of said first and second lattice substructures under a load applied to said lattice structure along said predetermined energy absorbing load vector occurs sequentially rather than concurrently, thereby enhancing an energy absorbing capacity of said lattice structure. 
     
     
         8 . The lattice structure of  claim 7 , wherein the struts that are substantially perpendicular to said predetermined energy absorbing load vector are excluded from said second lattice substructure. 
     
     
         9 . The lattice structure of  claim 1 , wherein said first and second lattice substructures are defined by a tetrahedral mesh or a hexahedral mesh. 
     
     
         10 . The lattice structure of  claim 9 , wherein said first and second lattice substructures are defined by the tetrahedral mesh, and
 wherein:   (a) said first set of interconnected struts interconnect centroids of adjacent tetrahedra of said tetrahedral mesh to one another; and   (b) said second set of interconnected struts interconnect a centroid of each tetrahedron of said tetrahedral mesh to four vertices thereof.   
     
     
         11 . The lattice structure of  claim 10 , wherein:
 (a) said first set of interconnected struts interconnect the centroid of each tetrahedron of said tetrahedral mesh to the four vertices thereof; and   (b) said second set of interconnected struts interconnect the four vertices of each said tetrahedron of said tetrahedral mesh to one another.   
     
     
         12 . The lattice structure of  claim 10 , wherein:
 (a) said first set of interconnected struts interconnect the centroids of adjacent tetrahedra of said tetrahedral mesh to one another; and   (b) said second set of interconnected struts interconnect the four vertices of each said tetrahedron of said tetrahedral mesh to one another.   
     
     
         13 . The lattice structure of  claim 1 , further comprising:
 (a) at least a third lattice substructure, interwoven with said first and second lattice substructures, and optionally interconnected with one or both thereof.   
     
     
         14 . A shock absorber, cushion, or pad comprised of t lattice structure of  claim 1 . 
     
     
         15 . A wearable protective device, bed, seat, automotive or aerospace panel, bumper, or component comprising the shock absorber, cushion, or pad of  claim 14 . 
     
     
         16 - 17 . (canceled) 
     
     
         18 . A method of forming an energy absorbing lattice having a predetermined energy absorbing load vector comprising:
 providing a mesh comprising a plurality of polyhedra;   forming a first lattice substructure comprising a first set of interconnected struts that are defined by the mesh;   forming a second lattice substructure comprising a second set of interconnected struts that are defined by the mesh, wherein the second lattice substructure differs from the first lattice substructure;   generating a compound lattice structure by combining the first lattice substructure with the second lattice substructure; and   removing one or more struts from the compound lattice structure that are substantially perpendicular to the predetermined energy absorbing load vector, and/or that are substantially parallel to the predetermined energy absorbing load vector.   
     
     
         19 . The method of  claim 18 , wherein the one or more struts that are removed from the compound lattice structure are substantially perpendicular to the predetermined energy absorbing load vector. 
     
     
         20 . The method of  claim 18 , further comprising:
 manufacturing the compound lattice structure using an additive manufacturing process.   
     
     
         21 . The method of  claim 18 , wherein forming the first lattice substructure comprises forming a dual substructure by connecting centroids of adjacent polyhedra of the mesh. 
     
     
         22 . The method of  claim 18 , wherein forming the second lattice substructure comprises forming a rhombile tessellation substructure by connecting a centroid of each polyhedron of the mesh to corners of the polyhedron. 
     
     
         23 . The method of  claim 18 , wherein the first lattice substructure and the second lattice substructure are interconnected with one another. 
     
     
         24 . The method of  claim 18 , wherein the first set of interconnected struts and the second set of interconnected struts differ in diameter from one another. 
     
     
         25 . The method of  claim 18 , wherein the first set of interconnected struts comprises struts of differing diameters and/or the second set of interconnected struts comprises struts of differing diameters. 
     
     
         26 . (canceled) 
     
     
         27 . The method of  claim 18 , wherein the mesh comprises a plurality of tetrahedra or a plurality of hexahedra. 
     
     
         28 . (canceled) 
     
     
         29 . The method of  claim 27 , wherein the mesh comprises a plurality of tetrahedra configured in an A15, C15, or alpha space packing structure,
 wherein the first set of interconnected struts interconnect centroids of adjacent tetrahedra of the mesh to one another, and   wherein the second set of interconnected struts interconnect a centroid of each tetrahedron of said mesh to four vertices thereof.   
     
     
         30 . The method of  claim 29 , wherein the first set of interconnected struts interconnect the centroid of each tetrahedron of the mesh to the four vertices thereof, and
 wherein the second set of interconnected struts interconnect the four vertices of each tetrahedron of the mesh to one another.   
     
     
         31 . The method of  claim 29 , wherein the first set of interconnected struts interconnect the centroids of adjacent tetrahedra of the mesh to one another, and
 wherein the second set of interconnected struts interconnect the four vertices of each tetrahedron of the mesh to one another.